PPQs and Notes
Borneo’s Rainforest:
The third largest island in the world, historically covered by rainforest.
An area with high species diversity: 15000 plant species, 220 mammal species and 420 bird species.
The rainforest has been commercially logged since the 1970s for export markets, with logging accelerating in the 1980s and 90s.
Between 1974 and 1985 there was a 30% reduction in rainforest coverage.
The deforestation rate between 2000 and 2005 was 3.9% per annum.
Changes in forest structure reduce biodiversity.
Palm oil plantations (which is being planted on clear land) fragment rainforest, block migration routes and remove habitats for animals.
Without forest cover, soil erode making it impossible for vegetation to grow.
The valuable role that the ecosystem provides, through biodiversity and controlling weather patterns, has been reduced.
Climate change and biodiversity are inextricably linked - e.g., diverse forests absorb more carbon.
Food security - two thirds of food supply is obtained from a total of nine crops.
Clean air and water - Trees turn CO2 into oxygen. Plants use solar energy to grow. Shellfish purify the water. More biodiversity means more ecosystem services.
Natural resources - building materials and medicine are provided by nature.
Preventing diseases and pests - the loss of one species results in the loss of another as they are interdependent, and increased genetic diversity makes species less vulnerable.
Ethics - species are intrinsically valuable, therefore we are morally obliged to preserve their existence (ecocentric value system).
Variation. Organisms (within populations) exhibit individual variation in appearance and behavior. These variations may involve body size, hair color, facial markings, voice properties, or number of offspring. On the other hand, some traits show little to no variation among individuals—for example, number of eyes in vertebrates.
Inheritance. Some traits are consistently passed on from parent to offspring. Such traits are heritable, whereas other traits are strongly influenced by environmental conditions and show weak heritability.
High rate of population growth. Most populations have more offspring each year than local resources can support leading to a struggle for resources. Each generation experiences substantial mortality.
Differential survival and reproduction. Individuals possessing traits well suited for the struggle for local resources will contribute more offspring to the next generation.
IGO: intergovernmental organisation - uses treaties or actions involving two or more nations.
Can reach a large audience through working directly with the media.
Decisions made bureaucratically - can be a slow process due to consensus being a required from all members of the large organisation.
Decisions may be more politically driven than by sincere passion for conservation.
Uses intensive scientific research before taking extreme action.
Enforces mass-scale decisions via law which may be authoritarian in style.
Easy access to publication of guidelines and international agreements.
Using funding from a national budget.
Access both local and global populations with immediacy.
NGO: a non-governmental organisation; a non profit organisation that operates independently to government policy.
Acquires media coverage through extreme action - protests/campaigns.
Doesn't involve easy access mass funding or media coverage.
Enthusiasm and passion from members usually leads to dedication and quick responses.
Motivated entirely by conservation strategies.
Can hold extreme views which class with public or political opinion.
May be viewed as overly radical.
Relies on success of public pressure and manipulation rather than direct legal power.
Limited to local action such as buying and managing land.
Relies on private funding for environmental projects.
Only attracts attention from those who are already concerned by environmental issue.
Isolation plays a crucial role in the process of natural selection by creating separate gene pools that can evolve independently.
The Galapagos finches are a classic example of this, as different species of finches evolved on different islands due to geographic isolation - created by rising magma from breaks in the Earth’s crust.
Volcanic islands were formed as a plate moved over the hotspot.
Each population faced unique environmental pressures, leading to adaptations that allowed them to survive and reproduce.
Over time, these adaptations accumulated and led to the formation of distinct species that each fulfilled different environmental niches.
Thus, isolation can drive the divergence of populations and ultimately lead to the creation of new species through natural selection.
Population size (smaller populations are more prone to extinction).
Reduction in population size over time (indicates that a species is under threat).
Degree of specialisation.
Distribution
Geographic range and degree of fragmentation.
Degree of endemicity (if its only found in one specific area).
Quality of habitat (species are less likely to survive in poor habitats).
Trophic level (animals in higher trophic levels are more likely to go extinct).
In-situ:
Means ‘in the original place.’
Methods are carried out on site - such as in the wild).
Methods are applicable for large populations.
Experimental conditions are difficult to maintain.
Less expensive.
Doesn't require mass equipment; less labour intensive.
Requires a large area.
Ex-situ
Means ‘outside the original place.’
Carried out off-site - such as in a laboratory, botanical garden, zoo or aquarium.
Methods are applicable for small populations.
Experimental conditions can be easily maintained.
More expensive.
Requires specific equipment and is labour intensive.
Requires only a small area.
In-situ conservation is generally considered more effective as it involves the protection and preservation of species in their natural habitats. Ex-situ conservation, on the other hand, involves the removal of species from their natural habitats and placing them in artificial environments such as zoos or botanical gardens. While ex-situ conservation can be useful in certain situations, it is often less effective in the long-term preservation of species and their ecosystems.
Small population size (reduced gene pool).
Limited distribution.
High degree of specialisation (dietary needs)
Slow reproductive rate - K-selected species with a small number of young.
Non-competitive behaviour between species.
Long migration routes
Human pressure (hunting/trade/climate change.
Arguments for the existence of zoos include:
They conserve endangered species and preserve biodiversity through breeding programmes.
They act as a centre of education on the importance of biodiversity.
They can also be used as research centres for behaviours and nutritional requirements.
Arguments against the existence of zoos include:
Legislation is required.
It is a stressful environment for animals which involves them being taken from their natural habitat.
Animals can be exploited if zoos are over-commercialised.